I was stuck on this one for awhile and still did not get it right. The two easier variations are 1.Rc1+ Rc7?? and 1.Rc1+ Rc3. I won't comment on those - they are much more forced. I never could get through the 1.Rc1+ Kb8 variation completely on my own. After looking up the answer and working through it in subsequent circles, I began to appreciate this problem more.

Seeing that White's Queen could give check on b4 was alot different than giving check b5 was pretty easy. The key to the difficulty seems to be the c8 square. First it's where Black's King is, then Black is guarding c8 more times than it is attacked, then Black is guarding c8 once as it is being attacked once. At the same time the Black King is stuck in the corner, walking into a strange sort of back rank checkmate threat.

After 1.Rc1+ Kb8 2.Qb4+ Ka8 3.Bf3!+ Rxf3

I am now beginning to think I left something out of my Simultaneous Advantage post: tying down defenders. That is similar to immobilizing defenders, although they still have some movement available to them. Here is a simplified analysis of the above position.

Preexisting advantages:

All of Black's King's flight squares have been removed.

Black's Queen is tied down to the eighth rank to defend against the back rank checkmate threat Rc8#.

Black's Rook on c7 is tied down to the seventh rank to defend against Qb7#.

On Qe4! Black gets some advantages from the move:

Moving into capture - White's Queen is unprotected on e4

Giving a King flight square - b8

White gets advantages which are terminal for Black:

Forcing with check - this also implies "preventing counterattack" on White's King

So what tactic (besides the fork aspect) is going on in the move Qe4? It seems to me as a special case of attacking the defender: a enprise attack on a tied down defender. Although Black's Queen is hanging, I believe a tied down defender essentially is equivalent to a hanging piece. Here's an example:

White to Move

Qb7! forks both Black Queens. Although they defend each other, the Black Queens cannot simultaneously defend against the back-rank mate threat and capture White's Queen.

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I am getting a bit annoyed with this new blogger editor as it keeps adding lines, especially in bulleted sentences.**rolls eyes**. Perhaps WordPress is in my future...

Circle 3 Complete

I am sinking into shallow pattern recognition solving the circle checkmates. When I recognize it I slow myself down and deliberately calculate through it again. That is one of the problems with books: the answers don't punish incomplete variation thinking.

I have found two wrong answers, 513 and 524. The mating idea was right, it just took moremoves.

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For about a month I have had difficulty leaving comments on blogs. If it doesn't go to a comment page that never completely loads it asks me to login and in the process loses my comment. I find it really irritating that something that was working for years is broken.

Wednesday, December 27, 2006

Circle 2 Complete

I am beginning to wonder about these problems. Although they highlight my weak areas, some of the themes are obscure. For instance, how many opportunities do beginning/intermediate players have to use a double sacrifice? That theme is a bit of a mind-bender.

Sunday, December 24, 2006

Circle 1 Complete

As I circle through my checkmate problems, I have begun to categorize the themes that come up in the checkmates that I often get wrong.

Sacrifice not on the initial move

Quiet moves, especially not on the initial move

Opening lines to take away opponent's King flight squares

Interference, forcing opponent's pieces onto his own King's flight squares, especially not on the initial move

Overworked Defenders who are not overworked on or after the initial move

This leaves out taking extra moves to achieve mate, using squares beyond a1 through h8, or instantaneously promoting all of my pieces to Queens.

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I am working on a universal definition of the weakest part of my chess game. So far I have two possibilities: either the part of my game that I am scrutinizing at this timeor the more straightforward all parts of my game are very, very weak. This definition seems to apply to the majority of chess players, players at all rating levels as well. At least how they describe themselves ;-).

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I wanted to put in a good word for GM Eugene Perelshteyn's French Defense opening lecture on chessfm. It was immensely accessible and well thought out. Although I never play either side of that opening, it didn't matter. I have not read his related books, but I gather they are quite good for beginner through intermediate level players.

These lectures are one of the biggest reason I joined the ICC - to support them to keep doing it =). I hope to see more.

Sunday, December 17, 2006

Circling Around Again

Years after I began it, I am approaching problem 800 in 1001 Better Ways to Checkmate (Wohoo!). I missed a mate in two and took five minutes to see a mate in one. I am consistently going for longer mates or missing crisscross attacks completely. *Sigh*Although I still get in an occasional blitz game, it's only through blunders that I am in the 1300 range. I know playing lots of long games would help more, but in lieu of time considerations I am going to do a "holiday" 40 problem mini-circle out of medium difficulty checkmates from the book. On a more upbeat note it is good to see so many interesting posts on other chess blogs including new Knights - I will add your links soon.

Thursday, December 07, 2006

Thinking in chess

What is chess thinking anyway? I don't really know. Years ago I would attribute most everything to visual pattern recognition or calculation. That seems terribly simplistic now.

Here is a parallel question. What is thinking in wrestling, like they have in the Olympics? Clearly the sport is a test of physical strength. All wrestlers are fit from training, so what determines the winner seems like a combination of things: strategy, tactics, timing, and space, especially if you consider that a wrestler can lose or gain by getting out of boundaries depending on the situation. The brain must be doing something for wrestlers.

Back to chess. I picked up an old chess book and casually reviewed some problems. I did not do much better on the "Combinations" section than I did before starting the TCT circles. I am busy and my chess is suffering. Anyway, I went back to the section on "Delivering Mate" and I quickly sailed through the easy mates. The tougher mates were a little slower. Surprisingly I didn't really recognize any of them. One just didn't make sense. I must have been too tired to calculate. Either that or lazy!

The Mammoth Book of ChessProblem 11, page 29

White to Move

This wasn't any pattern I recognized. I put the book down for five minutes, had my mind completely elsewhere, then picked up the book again and had the answer: Qe8. Because f8 was attacked twice by White, it seems logical for Black to take the Queen, but alas that is followed by a double-check. I had to laugh, as the d6 square was attacked no less than four times by Black!

I find it peculiar that the answer quietly popped out of nowhere. It was not visual, either. It sort of seemed mechanical, like pieces moving, as if to indicate, "do this". That is the mysterious chess thinking I have no clue about. And I can't imagine anyone becoming a strong player without it in one form or another.